Many people feel that each day they have less and less time to do the many things that need to be done.

In fact - and this is no illusion - the days seem to be getting shorter.

On June 29 of this year, scientists measured the shortest day since the length of the day was recorded with precise atomic clocks in the 1960s.

Wednesday ended 1.59 milliseconds earlier than usual.

This was announced by the International Earth Rotation and Reference Systems Service (IERS), the organization responsible for global timekeeping.

The reason: the earth rotated around its axis faster than usual.

According to the records, the shortest day so far, July 19, 2020, was almost a tenth of a second longer than June 29, 2022.

Manfred Lindinger

Editor in the department "Nature and Science".

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So is the earth spinning faster?

On the long time scale - no.

In the early history of the earth, the days were much shorter than today.

1.4 billion years ago, days were just 18 hours and 41 minutes, according to 2018 calculations.

When dinosaurs roamed our planet 70 million years ago, a single day lasted 23 hours and 30 minutes.

Today it is an average of 24 hours until a new morning dawns.

The days used to be much shorter

The reason the days used to be shorter is because of the moon.

The moon moves very slowly away from us in a spiral orbit around the earth.

With lasers, an annual increase in distance of about 3.8 centimeters was measured.

This has also changed the strength of the tidal forces.

These not only lead to ebb and flow, but also slow down the earth's rotation, according to the current theory.

As a result, the days on earth are becoming longer and longer, on average by around one 74,000th of a second per day.

In recent years, the opposite trend has been observed.

The days are getting shorter again because the earth rotates faster.

Although the effect is minimal, it is so large that it can be precisely detected with atomic clocks.

But why is the Earth's rotation increasing?

Researchers don't have a definitive answer.

Some researchers, such as Dennis McCarthy, former director of the US Naval Observatory, suspect the melting of the glaciers at the poles to be the cause.

As a result, there is less pressure on the earth's crust.

The earth would become rounder.

And the round shape, similar to the pirouette effect in figure skaters, caused the earth to spin faster on its axis.

On the other hand, the earth's crust should rise at the polar regions because it is free of ice.

As a result, the earth should become thicker and therefore rotate more slowly,

The fluctuations over time have no noticeable effect on our everyday lives.

For IT and satellite communication systems, however, since they depend on exact time measurements.

The leap second was introduced to compensate for the slowing of the Earth's rotation.

To do this, all clocks are stopped for one second.

Leap seconds are usually set in June or December, the last one introduced in 2016.

The next possibility would be in December.